1 files changed, 104 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/mptcp/mptcp_lib.sh b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
new file mode 100644
index 000000000000..f32045b23b89
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
@@ -0,0 +1,104 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+readonly KSFT_FAIL=1
+readonly KSFT_SKIP=4
+
+# SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var can be set when validating all
+# features using the last version of the kernel and the selftests to make sure
+# a test is not being skipped by mistake.
+mptcp_lib_expect_all_features() {
+	[ "${SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES:-}" = "1" ]
+}
+
+# $1: msg
+mptcp_lib_fail_if_expected_feature() {
+	if mptcp_lib_expect_all_features; then
+		echo "ERROR: missing feature: ${*}"
+		exit ${KSFT_FAIL}
+	fi
+
+	return 1
+}
+
+# $1: file
+mptcp_lib_has_file() {
+	local f="${1}"
+
+	if [ -f "${f}" ]; then
+		return 0
+	fi
+
+	mptcp_lib_fail_if_expected_feature "${f} file not found"
+}
+
+mptcp_lib_check_mptcp() {
+	if ! mptcp_lib_has_file "/proc/sys/net/mptcp/enabled"; then
+		echo "SKIP: MPTCP support is not available"
+		exit ${KSFT_SKIP}
+	fi
+}
+
+mptcp_lib_check_kallsyms() {
+	if ! mptcp_lib_has_file "/proc/kallsyms"; then
+		echo "SKIP: CONFIG_KALLSYMS is missing"
+		exit ${KSFT_SKIP}
+	fi
+}
+
+# Internal: use mptcp_lib_kallsyms_has() instead
+__mptcp_lib_kallsyms_has() {
+	local sym="${1}"
+
+	mptcp_lib_check_kallsyms
+
+	grep -q " ${sym}" /proc/kallsyms
+}
+
+# $1: part of a symbol to look at, add '$' at the end for full name
+mptcp_lib_kallsyms_has() {
+	local sym="${1}"
+
+	if __mptcp_lib_kallsyms_has "${sym}"; then
+		return 0
+	fi
+
+	mptcp_lib_fail_if_expected_feature "${sym} symbol not found"
+}
+
+# $1: part of a symbol to look at, add '$' at the end for full name
+mptcp_lib_kallsyms_doesnt_have() {
+	local sym="${1}"
+
+	if ! __mptcp_lib_kallsyms_has "${sym}"; then
+		return 0
+	fi
+
+	mptcp_lib_fail_if_expected_feature "${sym} symbol has been found"
+}
+
+# !!!AVOID USING THIS!!!
+# Features might not land in the expected version and features can be backported
+#
+# $1: kernel version, e.g. 6.3
+mptcp_lib_kversion_ge() {
+	local exp_maj="${1%.*}"
+	local exp_min="${1#*.}"
+	local v maj min
+
+	# If the kernel has backported features, set this env var to 1:
+	if [ "${SELFTESTS_MPTCP_LIB_NO_KVERSION_CHECK:-}" = "1" ]; then
+		return 0
+	fi
+
+	v=$(uname -r | cut -d'.' -f1,2)
+	maj=${v%.*}
+	min=${v#*.}
+
+	if   [ "${maj}" -gt "${exp_maj}" ] ||
+	   { [ "${maj}" -eq "${exp_maj}" ] && [ "${min}" -ge "${exp_min}" ]; }; then
+		return 0
+	fi
+
+	mptcp_lib_fail_if_expected_feature "kernel version ${1} lower than ${v}"
+}